1. Field of the Invention
The present invention relates to refractory elements with self-contained air passages for combustion air and to heating apparatus using the elements.
2. Description of the Prior Art
It is common to use brick made of refractory materials to line stoves and provide dimensioned firepots. Such bricks have also been used to control the direction of airflow both to and from the combustion area. A recognized problem in burning fossil fuels is that usually a lot of the combustible material passes off through the flue as unburned gases. This reduces combustion efficiency and adds to pollution. Combustion apparatus today is designed to attempt to achieve a secondary burn in order to complete the combustion of what has formerly passed off as unburned gas. The problem is that most of this apparatus achieves the secondary burn only under optimum conditions and not under usual operating conditions. This is due to build up of ashes and addition of fresh fuel that interferes with proper aspiration and prevents the high temperatures necessary for the secondary burn.